[trularin]

Okay, short of it is, instead of 75 pounds of pressure to stop the car, all you need is 10.

As I remember it, the cuve is close to a line in the operating regions. When the pedal is pressed, the vaccum assist the rod to the cylinder. When you let off, there was a spring that retracted the diaphram.

I think you can address this as an asymtotic ( you really have to love my spelling ) equation with a long curve.

Something like e ** x. "e to the x"

I get the impression you are fixing the equation in the sheet. if this is correct, Why?